diplodocus.org Git - nmh/blob - sbr/uprf.c

   1
   2 /*
   3  * uprf.c -- "unsigned" lexical prefix
   4  *
   5  * This code is Copyright (c) 2002, by the authors of nmh.  See the
   6  * COPYRIGHT file in the root directory of the nmh distribution for
   7  * complete copyright information.
   8  */
   9
  10 #include <h/mh.h>
  11
  12 #ifndef LOCALE
  13 # define TO_LOWER 040
  14 # define NO_MASK  000
  15 #endif
  16
  17
  18 int
  19 uprf (char *c1, char *c2)
  20 {
  21     int c, mask;
  22
  23     if (!(c1 && c2))
  24         return 0;
  25
  26     while ((c = *c2++))
  27     {
  28 #ifdef LOCALE
  29         c &= 0xff;
  30         mask = *c1 & 0xff;
  31         c = (isalpha(c) && isupper(c)) ? tolower(c) : c;
  32         mask = (isalpha(mask) && isupper(mask)) ? tolower(mask) : mask;
  33         if (c != mask)
  34 #else
  35         mask = (isalpha(c) && isalpha(*c1)) ?  TO_LOWER : NO_MASK;
  36         if ((c | mask) != (*c1 | mask))
  37 #endif
  38             return 0;
  39         else
  40             c1++;
  41     }
  42     return 1;
  43 }